


I Can Feel Your Heartbeat

by UltimateGamer101



Series: UG101's Undertale One-Shots [2]
Category: Undertale (Video Game)
Genre: Alternate Universe - Underfell, Anxiety, Apologetic Sans, Cuddly Sans, Fear Play?, Fluff, Hurt/Comfort, I poke at angst with a stick, Multi, Other, Panic Attack, Scary Sans, Sorry Not Sorry, dubcon, not quite smut
Language: English
Status: Completed
Published: 2017-02-15
Updated: 2017-02-15
Packaged: 2018-09-24 14:00:55
Rating: Mature
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 2,025
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/9748424
Author URL: https://archiveofourown.org/users/UltimateGamer101/pseuds/UltimateGamer101
Summary: After a rough night of partying with the UnderFell crew, you awake to the presence of your spooky scary skeleton boyfriend... and things go a little too far.





	

**Author's Note:**

> So I'd intended this to be fluff for Valentine's Day, but then it got kinda smutty, but then it got too real and became angst... so now it's a hurt/comfort thing I guess xD

It'd been a wild night. Partying with the Fell group was more exciting than you remembered- most of the furniture had been destroyed the more drunk people got, and at _least_ half the house was utterly trashed. It would be a lengthy cleanup for Undyne, once she woke up, and anyone still present when she did so would be dragged into helping...

Fortunately for you, Sans had woken up early with that in mind, and had teleported the two of you onto his couch to keep snoozing. He wasn't getting roped into any activity he didn't hafta do, and nor was he letting you get roped into anything either. Why? He wasn't quite sure.

Maybe it was the softness of your sleeping body beneath his, like a comfortable, warm pillow. Yeah... that sounded about right. He just couldn't be bothered to get off of you before teleporting, so he brought you along with him. You wouldn't mind at all.

Heaving a relaxed sigh, the bulky skeleton laid his head down on your chest, content to go back to sleep...

* * *

You awoke to the sensation of warmth surrounding you, and sighed softly as you unconsciously snuggled closer. The semi-awake state you had attained, however, was interrupted by a deep chuckle of amusement, coming from... right on top of you??? Your body stiffened instinctively, and your eyes opened to stare down at the skeleton that was staring back at you.

"heya sweetheart. sleep well? have fun partying to hardy last night?"

You relaxed, releasing a huff of amusement as you nodded a confirmation. A slight blush was forming on your cheeks from the lazy gaze the skeleton had leveled upon you.

"Yep, to both questions. How about you? Sleep well?"

He grinned, his gold tooth gleaming in the dim lighting of a sunrise through the window.

"yup, sure did. although, strange thing. kept hearing a thumping noise from your chest. thought it might've been your soul, but souls generally don't thump like that. not unless they're experiencing somethin' ah... pretty deep."

His eyelights condensed, his gaze piercing your own with an unexpected heat as his grin sharpened. Slowly, he lowered his head back to your chest, resting the side of his skull down as he listened.

"well, would you listen to that? seems like that thumping is gettin' faster. got something to tell me, sweetheart?"

Your blush intensified at his gaze, and you fidgeted a little beneath his scrutiny, testing to see if you could sit upright. But, with his head down again, you were well and truly pinned. His question kept the blush going, at least.

"O-oh, that's probably my heartbeat... It speeds up according on certain stimuli, which can be physical or emotional. For example, it could speed up if I had just been choked, rapidly bringing oxygen and nutrients to my cells so I can recover quickly. It could also speed up if I were happy, excited, scared, or various other emotions."

The skeleton on top of you hummed thoughtfully, a low rumble you could feel in your chest. When his arms wrapped around your middle, pinning your own arms to your sides, your heartbeat sped up slightly. The warmth from earlier increased as well, by just a few degrees, and you shifted a little beneath him. Interesting...

"so your heartbeat is faster now. i wonder what that could mean..."

He lifted his head slightly, gazing up at your heated face with sharp eyelights.

"...i wonder if it's speeding up because you're aroused...? let's test that out, shall we?"

Your own eyes widened at that statement, mouth opening in some attempt to make a statement of denial, and he brought up a finger to rest lightly upon your lips.

"shhhh, don't even try to lie to me, sweetheart. i can smell ya from here. you've just been pent up a while, now haven't you?"

A flash of darkness overtook your vision as he teleported you somewhere, and when light returned, you glanced around to find yourself in his bedroom. He'd never let you in there before... and for a good reason. It was hot, and messy, and had a very thick musky scent to it, like it hadn't been cleaned in months. Knowing him, that was very probable... it made you aware of his scent all the more, though.

"U-um, are you s-sure about this? We haven't..."

A ribbon of red magic floating above you drew your attention, and your question trailed off, mouth closing in order for you to gulp. It was true, you and him had been dating for quite some time, but you hadn't had sex yet. You hadn't had sex at all actually, still being a virgin, and you'd intended on waiting until you were Bonded with him to do anything like that. He'd put it off, but... maybe he was ready now?

"Sans..."

His hands wandered your sides, ribbons of red magic swaying behind him in an odd pattern you couldn't quite discern as he lay on top of you.

"don't you worry, toots. i know what you want."

A thumb slid beneath your waistband, rubbing slow circles on your hip, and you gasped quietly with the increasing warmth in your middle. Your hands made to intercept his, but you couldn't move them- a glance upwards revealed one of his magic tendrils had wrapped them firmly in place at the top of the bed.

"S-Sans...?"

The tempo of your heartbeat was increasing, and he grinned wider hearing it do so, a thrill running through his magic at the knowledge that _he_ was the cause of such a reaction. Pleased with himself, he sent a tendril of magic into your chest, wrapping it securely around your soul and gently tugging it out... Your vision grew somewhat hazy with your soul within his grasp, and you tugged at the magic ribbons around your wrists, suddenly feeling a little uneasy.

"W-What're you d-doing...?"

His thumb rubbed circles lower, putting pressure on unusually sensitive skin, and your breathing noticeably picked up in soft pants. The grin on his face was downright predatory as his magic brought your soul closer to him...

You gasped as his tongue swiped roughly across the surface of your soul, the tip curling around the bottom as the magic tendril faded away. The hot sensation of his breath against your soul warmed your entire body, and you couldn't stop a mewl of surprised pleasure from escaping your lips as his tongue wrapped fully around it. Your eyes closed for just a second, but a sudden squeeze had them snapping open again, your glassy gaze meeting his sharp one.

"heh, so cute... i could just eat you up. in fact, you probably want that, don't you?"

You shook your head, panting in a confused haze of arousal and fear as his tongue tugged your soul into his mouth. His teeth remained open, allowing you to see your soul as he rubbed it against the invisible roof of his mouth, and your body jerked in a spasm of pleasure.

"S-S-Saaaans-"

His teeth snapped shut, and a tendril across your lips muffled the shriek that begged to be heard in response. You began to feel real fear, heartbeat racing as your skeletal boyfriend swallowed your soul, and the sensation of being caught in a soft, tight area overcame your senses. A low chuckle was heard from a distance as you struggled, your pounding heartbeat making it difficult to hear him speak.

"what a tasty treat... don't worry, you'll get your soul back soon. after all, where the soul goes, the body must follow..."

You could barely feel the hand dipping down within your pants in the panic that had overcome you, but you knew that your struggling was as good as useless at this point. With your mind compromised by the pleasurable haze of your soul, your body was greatly weakened. However, you could certainly feel the tendrils of magic wrapping around your limbs and holding you firmly in place... 

Your panic increased, tears flowing down your cheeks and breath picking up to unhealthy speeds from the fear pulsing through your body. Noticing this, the skeleton straddling your middle began to send out soothing pulses from his own soul, slowing down and bringing his wandering hand up to cup your cheek.

"hey, hey, it's okay... i'm not gonna hurt ya... this is how monsters Bond, remember? the magically weaker monster's soul is temporarily housed in the body of the stronger one, so the wavelengths of the two souls can sync up together... i'm not gonna hurt you, i promise."

The terrified stutter to your soul began to ease, but you couldn't stop a fearful whimper from escaping your lips as your gaze frantically searched his own for any signs of falsehood. Not finding any, your body relaxed slightly, but you were nowhere near ready for what your boyfriend had in mind. Seeing this, he released you from his magic, allowing you to scramble up and away into a sitting position against the headboard, panting for breath. He'd really fucked up...

"shhh, shhhh, it's okay... i understand... i went too far. i'm sorry..."

As you gradually calmed down to the soothing pulses of emotion and whispered reassurances of your boyfriend, your breathing evened out, and you let him close the distance between the two of you. His arms slid around your waist, carefully leaving you with full arm movement, and he hummed a low melody into your chest as he listened to your heartbeat. Several moments passed before he deemed himself worthy of speaking again.

"sweetheart, i am so, so sorry... i didn't know you'd get this scared..."

The worst of your panic passed, you swallowed slowly, trying to get rid of the lump in your throat so you could speak.

"S-so you still would've wanted me to be afraid anyways? You're a real asshole, y'know..."

Your voice cracked at the end, but you managed to convey a sense of humor, an attempt to banish the remaining vestiges of fear still lacing the deepest parts of your thoughts. His relieved chuckle showed that he understood that, and you slowly allowed your arms to wrap around his shoulders to return the hug, sighing softly as he squeezed you in reassurance.

"yeah, i am. but 'm _your_ asshole... don't be afraid to tell me when things are too much for you in the future, okay? 'course, i'll prolly know, cuz we'll be Bonded soon... unless..."

He swallowed audibly, squeezing you closer as he pushed himself to say the next words.

"unless you don't want that anymore?"

You took a moment to think, allowing your arms to rest heavily upon his back as you closed your eyes. He drew back slightly to look at your face, more sweat beading on the back of his skull the longer you thought, terrified of what your response would be. Would you reject him? It would be perfectly justified, in fact, it was what he _expected_ , he'd just _fucked up that badly_...

After a few moments, you brought a hand up to his cervical vertebrae, pulling him forward until the side of his skull was flush with your chest. There you held him, his eyelights darting around in a confused manner- he'd expected you to ask for your soul back immediately, what was this?- and there you kept him for several moments as you collected your thoughts.

"Listen to my heartbeat, Sans. What does it sound like?"

He pressed himself closer, desperate to listen, to understand.

"it's slowed down... it sounds heavier... slow, but steady..."

You nodded, soothingly rubbing the back of his skull. The big bad monster wasn't so big and bad, especially when it came to you. He just tended to forget that sometimes, and get carried away, like he just had. It was a part of his personality, and while it may take you by surprise sometimes, you'd accepted and even enjoyed it before. One mistake wasn't worth giving him up.

"That's right. Slow and steady. I trust you."

He looked up at in disbelief, his teeth downturned and slightly parted in his uncertainty.

"I trust you..."


End file.
